javascript - 达到字符限制时删除字符或在退格上启用禁用 div

Question

在达到最大字符限制时，我们有一个禁用的 div，需要在退格上启用。但是现在我们没有在 iPhone 中获得退格的 ASCII 码。我怎么能检测到 div 的退格键。这是我在 Query 中的字符限制代码，需要启用才能删除字符：

<script>
var charlimit = 20;
var maindiv = 'content';
var charlendiv = 'myDiv';
$().ready(function()
   {
    var div = document.getElementById (maindiv);
    var text = $(div).text();
    document.getElementById(charlendiv).innerHTML = charlimit - text.length;
        $('#'+maindiv).keypress(function(e)
             { 
        var div = document.getElementById (maindiv);
            var text = $(div).text();
        var code = e.keyCode || e.which;
        if (text.length < charlimit) 
             {
          div.contentEditable = true;
         }
        else
              {
           div.contentEditable = false;
           if(code=='08' || code=='46' || code=='')  //ASCII code not detect by keyboard back space
                {
             div.contentEditable = true;
             }
         }
    });
    $('#'+maindiv).keyup(function(e)
       {
        var code = e.keyCode || e.which;
        var div = document.getElementById (maindiv);
        var text = $(div).text();
        document.getElementById(charlendiv).innerHTML = charlimit - text.length;
    });
});
</script>

Answer 1

The div has been disabled so none of your key will work now. Better approach is not to disable the div, instead you can opt for changing color of the div when limit has reached.